IP Library Granted Patent US 12667612
Granted Patent B2
US 12667612 · App. 18/143,547 · Granted Jun 30, 2026

MDCK suspension cell lines in serum-free, chemically-defined media for vaccine production

Inventors: Jenny Bang (Santa Ana, CA); Hsiao-Tzu Ni (Santa Ana, CA); Alan Yung-Chih Hu (Zhunan Town, TW); Tsai-Chuan Weng (Zhunan Town, TW)
Assignees: NATIONAL HEALTH RESEARCH INSTITUTES; FUJIFILM BIOSCIENCES INC.
A61K39/145A61K39/12C12N5/0686C12N7/00C12N15/8509A61P31/16C12N2015/8518C12N2500/90C12N2500/99C12N2511/00C12N2513/00C12N2517/02C12N2760/16034C12N2760/16051C12N2760/16134C12N2760/16151C12N2760/16251
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Quick Facts
Patent No.
US 12667612
App. No.
18/143,547
Granted
Jun 30, 2026
Kind
B2
Abstract

Disclosed is an adapted Madin-Darby canine kidney cell line capable of suspension culture in the absence of serum, and a chemically-defined medium for culture of the adapted MDCK cell line. Further disclosed are culture methods for growing the adapted MDCK cell line and methods for producing a vaccine from the adapted MDCK cell line grown in the chemically-defined medium.

Claims (19)

1 . A method of culturing suspension-and serum-free-adapted Madin-Darby canine kidney (MDCK) cells comprising contacting suspension-and serum-free-adapted MDCK cells (i) without microcarriers; and (ii) with chemically-defined and animal-component-free-growth medium, wherein the contacting is between about 1 day and about 12 days without medium exchange, wherein the chemically-defined and animal-component-free-medium comprises about 20 mM to about 30 mM glucose, wherein the culturing is suspension culturing at 5% CO 2 .

2 . The method of claim 1 , wherein the chemically-defined and animal-component-free-growth medium further comprises one or more amino acids selected from L-Serine, L-Arginine HCl, L-Leucine, L-Tyrosine 2Na 2H2O, L-Isoleucine, L-Threonine, L-Valine, L-Cysteine HCl H2O, L-Aspartic Acid, L-Glutamic Acid, L-Asparagine, L-Phenylalanine, L-Histidine HCl H2O, L-Methionine, L-Alanine, or L-Tryptophan.

3 . The method of claim 1 , wherein the suspension-and serum-free-adapted MDCK cells are deposited as DSM ACC3309 with Leibniz-Institut DSMZ-Deutsche Sammlung von Mikro-organismen und Zellkulturen GmbH.

4 . The method of claim 1 , wherein the suspension-and serum-free-adapted MDCK cells have an average doubling time of between about 30 hours and about 35 hours.

5 . The method of claim 4 , wherein the suspension-and serum-free-adapted MDCK cells are suitable for producing virus for a human vaccine.

6 . The method of claim 5 , wherein the virus maintains antigenicity.

7 . The method of claim 6 , wherein the virus is an influenza virus.

8 . A method for producing and culturing an isolated suspension of a serum free adapted Madin-Darby canine kidney (MDCK) cell line comprising:

(a) contacting adherent MDCK cells with a growth medium comprising between about 1% v/v to about 20% v/v serum for a period of time sufficient to establish the adherent MDCK cells in culture;

(b) contacting the established adherent MDCK cells with increasing amounts of chemically-defined growth medium and decreasing amounts of the serum serially until the chemically-defined growth medium does not comprise serum and represents all of the medium;

(c) isolating the adapted MDCK cells thereby producing an isolated suspension of a serum free adapted MDCK cell line; and

(d) culturing the isolated suspension of a serum free adapted MDCK cell line between about 1 day and about 12 days with a chemically-defined and animal-component-free-medium without medium exchange and without microcarriers.

9 . The method of claim 8 , wherein the established adherent MDCK cells of (b) are agitated and in the absence of microcarriers.

10 . The method of claim 9 , wherein the isolated suspension of a serum free adapted MDCK cell line is deposited as DSM ACC3309 with Leibniz-Institut DSMZ-Deutsche Sammlung von Mikro-organismen und Zellkulturen GmbH.

11 . The method of claim 9 , wherein the growth medium of (a) comprises 5% serum.

12 . The method of claim 11 , wherein the serum is fetal bovine serum (FBS).

13 . The method of claim 12 , wherein the isolated suspension of a serum free adapted MDCK cell line is suitable for producing a virus for a vaccine.

14 . The method of claim 13 , wherein the isolated suspension of a serum free adapted MDCK cell line has a doubling time of between about 30 hours and 35 hours.

15 . The method of claim 14 , wherein the culturing is in suspension at 5% CO 2 .